Web spreader element

ABSTRACT

A SPREADER ELEMENT WHICH IS USEFUL TO SPREAD A WEB INCLUDES AN ADJUSTABLE BOWABLE SHAFT AND A CYLINDRICAL NON-ROTATABLE OUTER SURFACE ABOUT THE BOWABLE SHAFT. ACCORDING TO THE PRESENT INVENTION, THE OUTER CYLINDRICAL SURFACE IS MADE UP OF A PLURALITY OF SEPARATE CYLINDRICAL SEGMENTS AXIALLY ALIGNED ALONG THE SHAFT EACH SEGMENT BEING NON-ROTATABLE RELATIVE TO THE MEMBER.

March '6, 1973 K. G. FRYE 3,719,315

WEB SPREADER ELEMENT Filed April 22, 1971 2 Sheets-Sheet 1 Fla. 1

INVENTOR KENNETH G. FRYE ATTORNEYS 2 Sheets-Sheet 2 K. G. FRYE WEB SPREADER ELEMENT &

INVENTOR KENNETH G. FRYE A mm 2 M? Q N M .F

a w wt 5 T 2 1. E CQA a7 AT TMYS March 6, 1973 mm vm A b m United States Patent 3,719,316 WEB SPREADER ELEMENT Kenneth G. Frye, Downingtown, Pa., assignor to Beloit Corporation, Beloit, Wis. Filed Apr. 22, 1971, Ser. No. 136,378 Int. Cl. B65h 23/32 US. Cl. 226-199 3 Claims ABSTRACT OF THE DISCLOSURE A spreader element which is useful to spread a web includes an adjustably bowable shaft and a cylindrical, non-rotatable outer surface about the bowable shaft. According to the present invention, the outer cylindrical surface is made up of a plurality of separate cylindrical segments axially aligned along the shaft each segment being non-rotatable relative to the member.

BACKGROUND OF THE INVENTION This invention relates to a web spreader element. More particularly, the invention relates to a spreader which comprises a shaft which is adjustably bowable and a non-rotatable cylindrical outer surface mounted on the shaft. Even more particularly, the invention relates to such a spreader wherein the outer cylindrical surface comprises a plurality of individual hardened or nonhardened ring segments.

In the production of web material, such as paper, large machines are often used to produce the material in a continuous web form. In view of the large size of the machinery, the sheet is frequently quite large and very often too large to be utilized directly. For example, in the manufacture of paper, it is not unusual to produce paper in the form of a roll having a width of thirty feet and a diameter of nine feet. Paper rolls of this size are not normally directly useable. For example, in the case of newsprint, the rolls used by the printer are much smaller both in width and in diameter.

While in the foregoing paragraph, and hereinafter, reference will be made to paper, it is to be understood that while the invention has particular suitablity to the manufacture of paper, it has general applicability to any web material, particularly those web materials which are normally produced in a continuous web in large and small sized rolls.

In order to reduce the size of the paper roll, the large roll is usually re-wound onto a plurality of axially aligned cores of suitable length on a re-wind device. As the paper is wound from the large roll onto the cores, the paper is slit lengthwise to form a plurality of webs of proper width. The width corresponds to the length of the core on which the particular-web is wound. Overlap of paper between adjacent rolls on the re-winding device obviously cannot be tolerated and, for this reason, the slit paper is spread out, fan-like, by means of a spreader. A conventional spreader can be either a roll comprising an adjustably bowable shaft and a cylindrical outer surface mounted for rotation about the bowable shaft, on a D-bar (description later). A widely used spreader roll 3,719,316 Patented Mar. 6, 1973 roller. The D-bar on the other hand is a bar its cross section being in the form of a D with individual adjustment every 3 to 12" across the machine. This flexible bar is adjusted in such a way as to spread a multiplicity of webs with the optimum adjustment being one of uniform curvature of the bar. While devices of this type are widely used, they are generally unsatisfactory in several respects.

The paper which passes over the spreader roll is, of course, of relatively low mass. On the other hand, the spreader roll, and the outer surface thereof, is of relatively high mass. A web passing over the spreader roll frequently induces an air film between the web and the spreader roll surface and this loss of traction causes a difference in speed between the web and the spreader roll. When this difference in speed becomes substantial, it is possible for the web to change the effective grip on the spreading device and consequently spreading is not accomplished and interweaving occurs. Therefore, massive rotating spreader roll elements, such as the rubber-canvas composition mentioned, are usually driven at web speed which requires a relatively complex device. A paper roll of large diameter is normally utilized to form several rolls of small diameter. In a non-continuous Winding operation, as each smaller roll is completed, the machine must be slowed down on occasion and stopped, the wound roll removed, a new set of empty cores positioned on the rewinder, and the re-winding operation then commences. Each time the paper is stopped or change of speed occurs, the heavy outer cylindrical surface of the spreader roll must also be stopped or there is a chance that the paper will lose contact with the spreading device and interweaving will occur.

The D-bar on the other hand has a plurality of adjustments spaced across the bar. Since the optimum method of spreading incorporated uniform curvature of the bar, it is readily apparent that the operator cannot adjust this how to a uniform curvature and consequently the paper interweaves.

It is an object of the present invention to provide a spreader element which functions as the conventional spreader but which is free from the disadvantages mentioned above. It is a further object of the invention to provide a spreader having a non-rotatable outer cylindrical surface. It is a further object of the invention to provide a spreader having a non-rotatable outer cylindrical surface which is segmented.

BRIEF SUMMARY OF THE INVENTION The foregoing and other objects which will be apparent to those having ordinary skill in the art are achieved according to the present invention by providing a spreader roll comprising a bowable shaft, means for adjustably bowing said shaft, and a plurality of cylindrical rings individually mounted along said shaft and secured thereto to prevent rotation thereof relative to said shaft, said rings each having a cylindrical ,outer surface of equal diameter, said outer surfaces being in axial alignment forming a generally continuous cylindrical spreader roll surface capable of being adjustably bowed, and being spaced apart along the length of said shaft a distance sufficient to permit bowing of said shaft, said spreader roll surface comprising said plurality of non-rotatable cylindrical surfaces. However, it is to be understood that the detailed description and accompanying drawings are provided solely for the purpose of illustrating a preferred embodiment and that the invention is capable of numerous modifications and variations apparent to those skilled in the art without departing from the spirit and scope of the invention.

FIG. 1 is a diagrammatic view of a rewinding device including a web spreader according to the present invention;

FIG. 2 is an elevation of a web spreader according to the present invention; and

FIG. 3 is an enlarged view of a portion of the web spreader of FIG. 2.

DETAILED DESCRIPTION A spreader according to the present invention is utilized in a re-winding device shown generally in FIG. l. A roll 1 of paper is slit by knives 2 to form a plurality of webs having a width less than the width of the original roll. In the simplified version shown, the original roll is split such that four rolls of equal width are obtained. The roll is wound from the large roll 1 on to a plurality of cores 3 axially aligned in the nip formed between re-wind rollers 4 and 5. A single end of one core 3 is shown in the drawing for simplicity. Each core is thus Wound with a roll of paper 6 having a width corresponding to the length of the core. The width is established by the positions of the knives 2 which, in turn, are selected depending upon the size width of the rolls desired to be produced. Overlap between layers of paper on adjacent re-wound rolls 6 cannot be tolerated in a device of this type. Accordingly, the slit paper is passed over a spreader 7 in order to spread the slit paper prior to rewinding. The spreader according to the present invention comprises an adjustably bowable shaft over which is mounted a nonrotatable cylindrical outer surface. On passage over the bowed spreader, the same air film is developed. However, in this case the sliding surface is lubricated by the air and can be enhanced further by the introduction of air for slower speeds. At no time is there a change of relative speed between the web and bar. Thus consistent contact is formed between the web and the cylindrical surface and the individual portions of the web 8 are spread apart in a fan-like manner. Thus, a gap 9 appears between adjacent webs thus forming a suitable gap 10 between adjacent rolls 6 formed on the re-wind rollers 4 and 5. The device is also provided with conventional means not shown to drive the various rollers and to retain the cores 3 and roll 6 in accurate alignment on the rewind rollers 4 and 5.

Spreader 7 according to the present invention is shown in detail in FIG. 2. Many methods are and can be applied to bow the bar uniformly. One such device comprises a shaft 11 which is split into two portions 11' and 11" by virtue of a slit 12 extending through the shaft from end 13 to a point 14 located adjacent the opposite end portion 11 of the shaft, said opposite end being solid. The shaft is adjustably bowable in the direction of arrow 15 by means of a pin 16 which is movable in a cavity 17 located in end 13 of the shaft. The cavity 17 is concentric with the shaft and includes a bottom wall 18 against which the pin bears. The inner section of pin 16 is partially cut away such that the pin 16 contracts only shaft portion 11 of surface 18. End portion 11 of shaft 11 is fixed to a sleeve 19 by welding or other means and sleeve 19 is, in turn, fixed to a bearing 20 of known type which comprises bearing member 21 movably mounted within fixed bearing member 22 which supports that end of the shaft. A similar bearing 23 comprising members 24 and 25 supports the other end of the shaft. Pin 16 can be biased against surface 18 by means of a ram 26 which is operated by a hydraulic system which is not shown for purposes of simplicity. The hydraulic fluid is introduced between ram 26 and a housing 27 defining a cylinder for the ram. Hydraulic pressure bet-Ween housing 27 and the ram 26 causes the ram to move to the left in the sense of FIG. 2 which, in turn, causes pin 16 to move to the left and bear against surface 18 of portion 11" of shaft 11. Since the pin bears against portion 11" of split shaft 11, the shaft is caused to bow in the direction of arrow 15 as shown. Pin 16 is keyed in cavity 17 to prevent rotation thereof.

The shaft is mounted in any convenient manner and preferably includes spherical mounting members 20 and 23 which do not impede bowing of the spreader and which permit rotating adjustment of the shaft to change the location of the bow relative to the unbowed shaft axis.

According to the present invention, the adjustably bowable spreader is provided with a plurality of non-rotatable segments 28 having cylindrical outer surfaces and axially aligned along the shaft. Each segment presents an outer cylindrical surface 29 which is not rotatable about the shaft. An individual segment is shown in more detail in FIG. 3 and, in BIG. 2, one of the segments has been shown in cross section to illustrate the manner in which each segment is secured to the shaft 11.

Each segment 28 comprises a ring 30 having a cylindrical inner surface 31 adjacent the shaft surface and an outer surface 29. Each ring segment is secured to shaft 11 by means of one or more set screws 32 or other suitable means (such as a key) to prevent rotation on the shaft. The inner surface 31 is preferably a close fit with the outer surface of shaft 11. A plurality of ring segments are provided along shaft 11 between end flanges 33 and 34. The rings are spaced along the shaft such that they do not unduly impede the bowing of the roll. Outer surfaces 29 of the ring segments are preferably smooth to enhance formation of an air rfilm between the surface and the web. The rings are preferably fabricated of a hardened metal but any metal can be used. The spreader can also be provided with means to introduce air between the web and outer surface 29. For example, compressed air can be introduced into a plenum 35 located behind each ring by means of a conduit 36 in shaft 11 and from the plenum to a plurality of apertures 37 in outer surface 29 by means of a conduit 38 in ring segment 28. Apertures 37 are, of course, located in that portion of the outer cylindrical surface of the spreader which is traversed by the moving web. The area which is traversed by the web will vary, of course, depending on web width, angle of web incidence, and the like, and the spreader preferably includes conventional valve means, conduit means and the like by which the size of the aerated surface area can be changed.

Accordingly, the spreader device according to the present invention is a non-rotatable roll member comprising a plurality of rings having a cylindrical outer surface of equal diameter. The outer surfaces are in axial alignment and are spaced apart along the length of the shaft a distance sufficient to permit bowing of the shaft and sufficient to form a generally continuous smooth cylindrical spreader roll surface.

The size of each segment can vary widely. The diameter thereof will depend to a large extent on the size of the operation, and will generally correspond to the diameter of conventional spreader rolls. The width of each segment can also vary widely depending upon the size of the operation. In most instances, the segments will be between one and twelve inches in width. -In general, the width of the segments is most logically to be as narrow as possible to simulate a continuous curved surface. In order to provide an effective spreader roll surface, at least 3 or 4 segments will be present beneath an individual slit sheet of paper. Therefore, segment width will be not more than /a or A of the width of the paper sheet passing thereover. The segments can be as small as desired, a practical lower limit being about 1 inch or /2 inch.

The spacing between segments should be sufficiently close to provide an effective spreader roll surface which is effectively continuous. However, the segments must not be placed so close together as to hinder bowing Within a given useful range. The spacing is clearly dependent upon the diameter and width of the segment as well as its elasticity, and no precise figures can be given. However, it is a simple matter to calculate the gap that will be necessary to permit unhindered bowing. The outer portion of the rings, of course, will generally be spaced apart further than the inner portions of the rings. The inner portions, in fact, can be quite close, particularly if fabricated from a resilient material.

While a particular type of bowable shaft has been described, it will be understood that other shafts can be used, such as those disclosed in US. Pats. Nos. 3,463,- 377; 2,689,392; 2,898,662; and 3,500,524 which are incorporated herein by reference.

What is claimed is:

1. A web spreader comprising a bowable shaft, means for adjustably bowing said shaft, and a plurality of cylindrical rings individually mounted along said shaft and secured thereto to prevent rotation thereof relative to said shaft, said rings each having a cylindrical outer surface of equal diameter, said outer surfaces being in axial alignment forming a generally continuous cylindrical spreader roll surface capable of being adjustably bowed, and being spaced apart along the length of said shaft a distance sufiicient to permit bowing of said shaft, said spreader roll surface comprising said plurality of non-rotatable cylindrical surfaces.

2. A web spreader according to claim 1 further including means for conveying air from an inner portion of said spreader through apertures in said outer surface to form an air film between said outer surface and a web moving in adjacency therewith.

3. A web spreader according to claim 2 further including means for guiding a web into adjacency with said curved surface.

References Cited UNITED STATES PATENTS 2,054,214 9/1936 Buss 26-63 2,637,891 5/1953 Sperry 2663 3,266,743 8/1966 Moser et al. 2663 X ALLEN N. KNOWLES, Primary Examiner US. Cl. X.R. 2663; 22697 

